Automatic control for reverse-lock mechanisms



, Feb. 25, 1930. c. P. cum 1,748,410

AUTOMATIC CONTROL FOR REVERSE LOCK MECHANISMS Filed May 29, 1924 3 Sheets-Sheet 1 INVENTOR A TTORNE Y Feb. 25, 1930. c. P. CIRAC 1,748,410

AUTOMATIC CONTROL FOR REVERSE LOCK MECHANI SMS Filed May 29, 1924 3 Sheets-Sheet. 2

- 1NVNT0R (VIA/M551 613.40 R

rogmsf Feb. 25, 1930. c P. CIRAC 1,748,410

- AUTOMATIC CONTROL FOR REVERSE LOCK MECHANISMS Filed May 29, 1924 5 Sheets-Sheet 3 INVENTOR Q E I By (IA/Hi5 fi CIR/1C A TTORNE Y PatenteclFeb. 25, 1930 CHARLES I. CIRAC, OF SAN FRANCISCO, CALIFORNIA AUTOMATIC CON TROL FOR REVERSE-LOCK MECHANISMS Application filed May 29,

The present invention is an improved automatic control for reverse lock mechanisms, such as is disclosed in Letters Patent of the United States Number 1,362,783 issued to Charles P; Cirac, on December 21, 1920.

This invention contemplates means, associated with an automobile transmission and responsive to any conventional type of gear shift mechanism, for automatically rendering operative or inoperative a mechanism designed to prevent reverse movement of said automobile. The value of such a lock for preventing backward movement of an automobile, independent of failure of brakes or engineor a faulty operation of either, is obvious and well recognized.

The principal object of this invention is to provide means, responsive to certain gear changes, whereby said lock will be of service -upon demand and will be instantly thrown out of engagement when no longer required, 'Other objects and-advantages will appear as this description proceeds. r

.' In this specification and the annexed drawings, the invention is illustrated in the form considered to be the best, but it'is to be understood that the invention is not limited to such form because it may be embodied in other forms, and it is also to be understood that in 80 and bythe claims followingthe description it is desired to cover the invention in whatever form it may be embodied. v

' In the accompanying three sheets of drawings, Figure 1 is a cross sectional view of a v 53 propeller shaft showing in elevation thereon a reverse lock and my control as the same "would appear from the rear, Figure 2 is a side elevation of Fig. 1, Figure 3'is an elevation reverse to Figure 1 and-shows means for connection with an automobile transmission housing,

F1gure4'1s a fragmentary top plan View of Figure 3 showing certain parts thereof asviewed from above, Figure 5 is an exploded view of Figure 2, I showing the component parts in side elevation in the positions they would assume if successively withdrawn, Figure 6 is a fragmentary top plan view,

- so i il to Figure 4, showing the parts in the 1924. Serial No. 716,500.

positions they would assume while the vehicle is reversing, v

F igure7 is a perspective view illustrating members of my automatic control, parts heing separated for the purpose of better illustrat-ion,

Figure 8 is a fragmentary view in elevation of a stationary member secured to the transmission housing and containing dogs, (this view is taken in the direction of the arrow VIII, of Figure 5,)

Figure 9 is'an elevation of a control plate, and the view is taken in the direction indicatedby the arrow IX, Figure 5,

Figure 10 is an elevation of a housing member and is taken in the direction indicated by the arrow X, Figure 5,

Figure 11 is a fragmentary top plan view of Figure 10, V

Figure 12 is a cross section, taken on line XII-XII of Figure 8,

Figure 13 is a section of a pair of slide members, the section line being indicated by the line XIII-XIII of Figure 4,

Figure 14 is an elevation of a ratchet plate, the view being taken as indicated by the arrow XIV, Figure 5,

Figure 15 is a diagrammatic view showing my control and a foot pedal for coaction therewith in a forward position,

Figure 16 is a view of a portion of Figure 15 as the parts would appear in a reversing position,

Figure 17 is a perspective view of a sliding latch member.

Figure 18 is a side elevation of a selector rod, the View being projected from Figure 15,

Figure 19is a side elevation of a selector rod, the View being projected from Figure 15,

Figure20 is a plan view of a slide member.

Referring to the drawings,Figures 1 and 2, the numeral lindicates a driven shaft, such as an autoinobilepropeller shaft, which is to be provided with'a lock preventing reverse rotation'ancl means controlling said lock. At 2 I show a circular disc member provided with a continuous flange 3, adapted to register with an opening in an automobile transmission housing and be secured thereto as by bolts through holes 1, the object being to secure said disc in stationary relation to said transmission. The disc 2 is provided with a plu rality of recesses 6, Figure 8, here shown as being quadrilaterally disposed in that face of said disc which is remote from the transmission. The purpose of these recesses is to re- I ceive dogs 7, illustrated in Figures 8 and 12.

These dogs are pivotally secured at one end on screws 8 and are urged outward at the opposite end by springs 9'.

The disc 2 is provided with a collarll, Figures 8 and 5, on which is rotatively mounted a control plate 12, Figures 5 and 9. This plate 12 is provided with apertures 13, corresponding in number with the dogs 7, and adapted,

. whensaid plate is rotated in onedirection on collar 11, to depress said dogs-into recesses 6, and when oppositely rotated, to permit the rise of said dogs, under urge of springs 9.

The control plate12 is'provided with a 1511-.

' ger 14 extending radially therefrom for coaction with partsto be later described.

At 16, Figures 5 and 14, Ishow aratchet plate or discprovided witlra central bore 17 to admit therethrough a sleeve 18, Figure 5, on a member 19. The ratchet plate 16 is secured by screws 20 to the disc 19 and both are intended to rotate with the shaft 1 because of the member 19 being keyed thereto, as shown at 21, Figure 1..

At 221 show an annular housing member adapted to form a close fit around'the member 19 and, when secured to disc 2, as by screws 23, to enclose in grease the dogs 7, control plate 12 and ratchet plate 16. The housing member 22 is cut away at the top, as is also the disc 2 to form a support for a plate 24 which is secured to disc 2. The top flat portion of the housing 22 is shown in Figure11,'wherein is shown a slot 26 for permitting a limited movement of the finger 14 on controldisc 12.

emember 22 over said finger.

plate 24, as by screws 28, Figure 4, are guide" A slot 27 communicates with slot 26 to permit the entrance and withdrawal of the housing Secured to the members 29 grooved at 31, to slidably engage a slide plate 32, The plate 24 is provided with a slot 33 registering with slot 26, Figure 7, through which extends the finger14.

The slide plate 32 is provided with anopening 34, Figures 4,6, 7 This opening is of a length sufficient to permit the sweep of finger 14 through the length of slot 33 and of a width, at one end, to provide a notch 36 for engaging said finger 14 when the same is in the reversing position showncin Figure 6.

At 37 I show an obllque cam surface form- .ing a part of the boundary of the opening 34.

In order to move the slide plate 32 to engage finger 14 in the different positions shown in Figures 4 and6, I'provide arslot 38,.in said plate, Figures 4 and 7 Extending into slot 38 is the bent end 39 of a member 41, the

threaded end of which is secured to a selector rod 42 of the transmission to which my device is attached. The purpose of slot 38 is to provide a lost motion connection whereby the member 41 may have a limited movement relative to the slide plate 32 when the selector rod is moved from a forward gear position to a neutral position on its way to a reverse gear position and vice versa.

t will be seen from the structure so far described, that, when the device is assemwbledas shown in' Figure 1, on a propeller shaft and secured to a transmission of an automobile, and the member 41 attached to a selector rod of the gear shift, each movement of the said selector rod will move in corre-.

sponding degree the member 41. Assuming that the said rod is in the forward gear position (Figure 4) the slot 38 will-be in the position7(relat ive to'member 41) shown in Figure 7 If the gear be shifted to a neutral position the member 41 will move toward the plate 32 but will impart no movement thereto the member 41moving until the end39 is in the opposite endof'said slot '38. At this time, if

another forwardqshift be made, the movementwill be reversed withoutchanging the position of plate 32. I

However, if a reverse gear shift-be made,

the member 41 (coming in contact with the end of slot 38) will move saidplate 32 to the position shown in Figure 6. Inthis position the fingerv 14 is engaged in notch 36 of said plateholding the control plate in a position where it retracts and holds the dogs 7 from engagement with teeth 9 ofthe ratchet plate 16, thus permitting a reverse vmovem'ent of the car, when in response to a' shlft to reverse position.

If a shift be made from reverse position to neutral position the movement just described will be reversed without any movement of plate 32 because of the lost motion'oonnection afforded by the length of slot 38 which afiords a permissible limit of travel .of the member It will be seen that the movement of "plate 32 to reverse position. (Figure 6) will throw finger 14 (should said finger be in locked position) because of the oblique cam surface 37 o,

in contact therewith.

The member 41is connected to that selector rod 42 which controls first'speedf (low) and reverse speeds. r

' I'will now describe mechanisinoperable in In Figure 13,1 showa means for yieldably yes ir'esponse to,.and associated with't-he other selector rod which controls second, and .third'(intermediate and high) speeds.

In Figures 7, l5 and 16 I show a pin secured to. slide 32 andcexten'ding upward through a slotin a member threaded intothe end of selector rod 40. The length of slot 50 is equivalent to the limit of travel of the selector rod 40 from second to high speeds.

pWhen selector rod 40 is moved to neutral position (indicated in dotted lines at N in Figure 15) the pin45 will be in the center of the length of slot 50. t

The purpose of pin 45 and member 55 is to provide means for'moving plate 32 from the position in which it is shown in Figure 16 to the one it assumes in Figure15 in order to release finger 14 to make the reverse lock automatically effective.

It will be seen that slide plate 32 can only get to position shown in Figure 16 in response to a reverse shift through selector rod 42 and member 41.

I will'now describe means by which said plate 32 will be returned to its position in Figure 15 in response to any forwardshift.

First, if selector rod 42 be moved to first speed ahead member 41 will engage in the end ofslot 38 and move said plate.

A movement of the other selector rod 40 to high-will also move plate 32 by reason of the pin 45engaging the end of slot 50.

. i It will be seen that the selector rod 40 must be moved backward from high to intermediate or second speed. In order to cause this retractive movement to the selector rod 40, to move plate 32 in'the opposite direction I provide a lever49 fulcrumed on a screw 51 secured to base plate 24. One end of lever 49 is provided with a slot through which extends a pin 52 secured to plate 32. The opposite end of lever48 is rounded and extends into the path of travel of selector rod 40. When 'saidfrod is shifted into second it abuts said lever, causingit to oscillate on it-spivot and thereby move plate 32.

The finger 14 is normally held at the left when the caris moving in a forward direction.- If noother means were provided for controllingthe movement of finger 14 the ratchet locking meansywould automatically free the car tomove forward and lock it against a movement backward. The controls described in this application are for the purpose of rendering the locking device inoperative when it is desired to reverse and the provision of means associated with, and responsive to, conventional gear shift mechanism 6 for doing this automatically; The only time that finger 14 is ever at the opposite (right) s'ide'of the slot in plate 32 is when the 'car is lockedagainst movement in a reverse direction. When so locked the first movement in a forwarddirection will return said finger 14 to its'normal position.

I will now describe means manually operated, independent of gear shift mechanism, for suspending orrendering inoperative the reverse lock.

I have described means responsive to all gear shifts for rendering the reverse lock mechanism inoperative, and now will describe means for doing sounder certain conditions where a shift of gears is inadvisable as, for instance, assuming that the vehicleis on an up grade and the driver desires to drop back without shifting to reverse, by releasing his clutch.

At 61 I show a slide member (shown in detail in Figure 20) which slides longitudinally in a groove 62 in base plate 24, Figure 7. This plate 61 is provided with an opening .63 corresponding in shape and length with slot 26, Figure 11, and with holes 64 and '66 for engagement with ends of springs 67 and 68 respectively. The end of spring 68 remote from slide 61 is secured to the frame 69, Figure 15, or any stationary part. t

The end of spring 67 remote from slide 61 is secured to one end of lever 71, fulcrumed at 72. Lever 71 carries on its end a roller 73 which n'ormally abuts the end of a plunger 74 slidable in a bearing 76 secured at 77 to the frame. a

The plunger 74 extends through the floor board 78 and is surmounted by a pedal 79. The pedal and plunger 74 are normally held in the position shown in Figure 15 by a spring 81 bearing at one end against said pedal and at the other end against floor 78. I If pedal 79 be depressed, lever 71 will move to its dotted line position placing spring 67 under tension. When this occurs, if the dogs 7 are not in contact with teeth'9, the slide 61 will respond to the urge of spring 67 and move to the position shown in Figure 16,'the slot 63 carrying finger 14 to the position shown in Figure 16.

However, should dogs 7 be in contact with teeth 9 (as when the vehicle is being held by the dogs 7 from backward movement down hill, at which time the weight of the car would cause contact between dogs 7 and'teeth 9 thus preventing movement of the control plate 12, the finger 14 of which extends through slot 63) the movement of slide 61 will be delayed and spring 67 will be put under tension until such time as thedogs 7 and teeth 9 disengage. Any slightmovement (forward) of the car will cause this dis- Thereupon the slide 61- will engagement.

position permitting carry finger 14 to the backing of thecar.

As the manual mechanism just described is only for a backing down movement of the I The latch-member '84 on guide member 29 by screws 86 extending through 'slots 87 which afford a slight move- -ment of 'said'iatch member relative to said screws.

car it is obvious that a latch means should be provided to hold slide 61 against its return should the manual means (pedal 79) be inadvertently released; Therefore, I "provide in slide 61 a notch 82 for engaging the 'edgeof a member 83 on "a sliding latch member'84.

is slidably mounted The latch member 84 is normally urged to "the positionshown in Figure 16 by a spring '88 'securedat one, end to guide member 29 and at the opposite end to a pin 89 in a hole '91 of the latch member.

iii)

It will be seen that when pedal 79 is depressed, slide 61 will move until stopped by the engagement of a pin-92 with guide member 29, at which time slot 82 registers w th latch member 83 which (under urge of spring 88) moves into said notch.

Latch-83'cannot be disengaged from plate 61 by any accidental release of the manual means (pedal 79) but can be released, auto matically, in several ways by the movement ofother parts as follows: First, in response to any forward movement of the car, as the finger 14moves to the positlon shown in Fig- ,ure 15, said finger encounters a cam surface 93 on latch member 84. As the surface 93 is oblique to the line of travel of said finger the finger will depress member 84 releasing latch 83 from notch 82; 7

ure 17, of latch member 84 which when moved also disengages latch 83 from notch Third, a shift to second speed will move selector rod 40 to a point where the end of said rod will contact with the end 96 of latch member 84 and move'same sufficiently to re-;

lease latch 83 from notch82.

The release of latch 83 from notch 82 by any of the means described leaves plate 61 free to return to the initial position, shown in Figure 15, underthe urge of spring 68, as-

suming that the greater urge of spring 67 has beenreleased by the release 'of'pedal 7 9.

, i The operation of the device is as follows WVhen the device is assembled 'asshown in Figure 1 and the member 41' is attached to the selector rod 42'of the'gej'ar shift for low and reverse speeds, each movement of said selector'rodwill move the member 41.

suming that the said rod is in the forWa-rd gear position the slot 38 will be in a position relative to the member 41 as shown in Figure If the gear shiftedto a neutral posi- *ti'on the mmber 41-will move toward the no effect upon the'plate' 32. I therefore that a movement of the plate 32 due plate but on account of the lost motion will impart no movement thereto until the end 39 is in the opposite end of the slot 38. At

this timeifanother forward shift should be made the position of the plat 32 ill t be changed. 2" 1 .7

' However, if thegear is shifted to reverse the member 41 Will'm'ovethe plate 32 to the positionsho'wnin Figure 6 with the'finger 14 ,located 1n the notch 36 of the plate 32 thereby holding the dogs 7 from engagement with the teeth 9 of the ratchet plate 16 thus permitting a reverse movement of the car in response to a shift of the gears to reverse position. v g i 7 Due to the lost motion in the slot 38 a shift being made to neutral position would have to placing the gear shift in reverse has-the effect to render the reverse mechanlsm inoperative.

It will be noticed The selectorrod 40 is associated with the 7 intermediate and high gear shift and by meansof the pin 45' operatinginthe slot 5 O of the member 55 the plate 32 can be moved from the position in which it is shown in'Figure 16 to that shown in Figure '15 inorder to release the finger 14 and render the reverse lock mechanism 'automatlcally end coming in contact with the selector rod 40. This causes the "rod 49t0' pivot and thereby. move the plate to the position shown in Figure 15.

V The manual mechanism operating the slide 61 is used when'lt is desired that the vehicle be moved backwardly without the necessity of shifting the gears to reverse. Depressing the plunger 74 through the slide lever v61 effective." When the selector rod 40 is moved backward. from-high to second speed the lever-40 ful-' crummed at41 is operated by the rounded places the'finger14 in inoperative position.

Means are also provided'tolockthe slide:61

until -.a forward movement of the car takes place and cause the disengagement ofthe latching mechanism for the slide 61.

T-claim:

1." The combination, with the powertransmission'and gear shift mechanism of an automobile, of a reverse lockmechanism', an automatic cont-rolmeans forsaid lock, responsive to conventional gear shift mechanism for,.se--

lectively, rendering said lock operative or inoperative, manually :operated means, inde pendent of said, automatic means, for actuatmg saidcontrol means to render said lock inoperative, and'rresilient. means, interposed between said control and said manual means,

whereby, should strainron the transmission prevent the movement of said control imme diately, said movement will take place as soon as said strain is removed. V V V o 2. The combination,with the-power transmission and gear shift mechanism of an auto-- inoperative, manually operated means, independent of said automatic means, for actuating said control means to render said lock inual means.

3. The combination, with the power transmission and gear shift mechanism of an automobile, of a reverse lock mechanism, an automatic control means for said lock, responsive to conventional gear shift mechanism, for, selectively, rendering said lock operative'or inoperative, manually operated means, independent of said automatic means, for actuating said control means to render said lock inoperative, resilient means, interposed between said control and said manual means. latch means for restraining said control means when actuated in response to said manual means, and means, automatically responsive to any forward movement of said automobile, for releasing said latch.

,4. The combination, with the power transmission and gear shift mechanism of an automobile, of a reverse lock mechanism, an automatic. control means for said lock, responsive to conventional gear shift mechanism, for, selectively, rendering said lock operative orinoperative, manually operated means, independent of said automatic means, for actuating said control means to render said lock inoperative, resilient means, interposed between said control and said manual means, latch means for restraining said control meanswhen actuated in response to said manual means, and means, automatically responsive to a shift of gears to second forward position, for releasing said latch and rendering said "reverse lock operative.

' 5'. The combination, with the power transmission and gear shift mechanism of an automobile, of a reverse lock mechanism, an automatic control for said lock, responsive to conventional gear shift mechanism, for, selectively, rendering said lock 0 erative or inoperative, manually operate means, independent of said automatic means, for actuating said control means to'render said lock inoperative, resilient means, interposed'between said control and said manual means, latch means for restraining said control means when actuated in response to said manual means, and means, automatically responsive to a shift of gears to reverse position, for releasingsaid latch and rendering said lock operative.

6. The combination, with the power transmission and gear shift mechanism of an automobile, of a reverse lock mechanism, and.

means responsive to conventional gear shift mechanism for, selectively, rendering said lock operative or inoperative, and positive means for securing said reverse lock in inoperative position when desiring to make a shift of gears to reverse position.

7. The combination, with the power trans mission and gear shift mechanism of an auto- .mobile, of a reverse lock mechanism, means responsive to conventional gear shift mechanism for, selectively, rendering said lock operative or inoperative, positive means for securing said reverse lock in inoperative position when desiring to make a shift of gears to reverse position, and means for maintaining said reverse lock in inoperative position when said gears are shifted from reverse to neutral position.

8. The combination, with the power trans mission and gear shift mechanism of an automobile, of a reverse lock mechanism, means responsive to conventional gear shift mechanism for, selectively, rendering said lock operative or inoperative, positive means for securing said lock in inoperative position when desiring to make a shift of gears to reverse position, and means, automatically responsive to a shift of gears to any forward speed position, for releasing said positive means and rendering operative said lock.

In testimony whereof I aifix my signature.

CHARLES P. CIRAC. 

